Apple posted a support document on its Web site addressing reports of interminable "blue screen" problems that caused some Mac users upgrading to Mac OS X Leopard no small degree of frustration. Apple said the problem could be related to "application enhancement software" that does not work with Mac OS X 10.5 Leopard. Apple recommended two solutions for Leopard owners attempting to upgrade: novice users should reinstall Leopard using the "Archive and Install" method detailed here. Other solution involves using the command line to get rid of the application enhancement software.

It offers integration if you don't go messing with the core of the OS. The products in question apply kernel patches. You shouldn't apply kernel patches to any OS, Windows and Linux included, if you don't know what you are doing. This still isn't an Apple problem, it's a user problem.